Although fans are almost certainly going to have their dreams of receiving a new spin-off to the Fallout franchise answered before a fifth game finally releases, it's probably not going to come in the form they all want.
Because, after the resounding success of The Elder Scrolls Online, it's more likely that the next big release in the series will be an MMO. Not only is that previously mentioned game doing extremely well for Bethesda, but the developer recently went on a hiring spree to target workers who could help build multiplayer and online systems.
Sure, these hires could be for a completely different project, but it's difficult to imagine either the main Elder Scrolls or Fallout titles implementing multiplayer anytime soon, pointing towards these new hires instead being put to work on a Fallout MMO.
An MMO based on the property has threatened to get off the ground for years, and in 2018 Bethesda needs to finally confirm whether or not it's actually happening.